Designing complex projects

• Designing complete transport systems
• Designing multimodal hubs
• Optimising transverse sections of tunnels

Sensitive integration into local environment

• dense urban environment with heavy road traffic ;
• historical and archaeological sites ;
• construction near to, or beneath, railway lines in operation.

Construction methods

SYSTRA has experience of a wide range of construction methods for underground structures according to the specifications and conditions of the site :

• open cut and cut-and-cover ;
• conventional tunnel construction methods for linear structures or stations ;
• tunnel-boring machines (open, earth, mud or compressed air-pressured) ;
• special methods : sub aquatic tunnel with submerged caissons, umbrella arch, repairs using sub-structures, ground treatment.

Work on existing underground structures

• Maintenance programme for tunnels and underground structures
• Repair and refurbishment of tunnels in operation

Geotechnology

• Tunnel calculation
  Estimating subsidence due to tunnel construction, using Plaxis software

• Incline calculations
  Calculating the stability of rail embankment inclines for the Beijing-Shanghai high-speed line project

• Longitudinal geological profile
  Ground studies (with supervision of bore-holes and tests) and ground treatment (compaction, drainage, injection)